海上风电大直径单桩基础优化研究

Optimal research on monopile for offshore wind farm

目前用于海上风电大直径单桩基础设计的API规范的p-y曲线法低估了土的初始刚度,导致设计过于保守。本文借鉴国际上关于大直径单桩基础桩土相互作用研究最前沿的PISA项目成果,采用能够真实反映大直径单桩基础受力模式的四刚度弹簧来模拟桩土相互作用,依托国家电投神泉一(二)期工程进行大直径单桩基础的优化研究,在满足频率、应力、变形、疲劳等设计指标的条件下,对单桩基础的入泥深度和壁厚进行了优化,所得设计桩重相比Ramboll方法可优化6%~7%,相比API方法可优化30%以上。

Currently,the p-y curve of API specification is used in the design of monopile for offshore underestimated the initial stiffness of soil,resulting in a conservative design.The optimal design of monopile is carried out in SPIC Shenquan I(II)project by the PISA method,which is the most advanced international research on pile-soil interaction of monopile.The pile-soil interaction is simulated by the four-stiffness spring reflecting the stress mode of the monopile.Under the condition of satisfying the design guideline such as freqs.,stress,deformation and fatigue,the thickness and the penetration depth of monopile are optimized.In this paper,the pile weight can be optimized by 6%~7%compared with that by the Ramboll method,and by more than 30%compared with that by the API method.